This object is achieved according to the invention by the filter in that an element axis of the at least one hollow filter element extends coaxially, axially, or in parallel to an installation/removal axis of the at least one hollow filter element, to which the hollow filter element can be installed through the at least one installation opening into the filter housing and removed from the filter housing in parallel, axially, or coaxially.
According to the invention, the element axis and the installation/removal axis at least extend in parallel in the mounted state. In this manner, the at least one hollow filter element can be easily installed axially in relation to the element axis in the at least one first housing part. Tilting or twisting of the at least one hollow filter element during the installation or removal is not necessary. Due to the axial arrangement of the hollow filter element, the second housing part, in particular a housing cover, can additionally be easily installed axially in relation to the installation/removal axis on or in the at least one installation opening for the closure thereof.
The installation/removal axis can advantageously be parallel, axial, or coaxial to a housing axis of the filter housing. The element axis can advantageously be parallel, axial, or coaxial to the housing axis during the entire installation procedure or removal procedure, at least from the entry into the filter housing, in particular into an installation opening.
The at least one hollow filter element can advantageously be arranged in the filter housing in relation to the at least one outlet and the at least one outlet such that at least one filter bellows can have flow through it from the radial inside to the radial outside or from the radial outside to the radial inside on the incoming-flow-side and/or outgoing-flow-side with respect to the element axis.
The hollow filter element can advantageously be a multiple-bellows hollow filter element having at least two filter bellows. The filter bellows can each comprise at least one filter medium, through which flow can occur for filtering the fluid.
The filter can advantageously comprise at least one pre-filter. The pre-filter can comprise at least one particle separator, in particular a cyclone separator. Particles, in particular dust, can be discharged from the inflowing fluid, in particular air, using the at least one particle separator. Thus, the amount of dirt which reaches the hollow filter element can be reduced. The service life of the hollow filter element can be lengthened in this manner.
The at least one pre-filter can advantageously comprise at least one cyclone block having a plurality of cyclone separators. The separation efficiency and/or the throughput capacity of fluid can thus be improved.
The filter, in particular at least one pre-filter and/or one particle separator, can advantageously have at least one guiding geometry. A fluid flow in the filter can be influenced using the at least one guiding geometry. A partial vacuum can be further quieted, in particular made more uniform, during operation of the filter using the at least one guiding geometry.
Overall, the flow profile in the filter having the at least one pre-filter can be approximately Z-shaped. In this manner, the filter can be adapted in a space-saving manner to the available structural space.
The at least one pre-filter can advantageously be connected by means of a flexible, in particular elastic connection, in particular a hose or folded bellows, to a main filter, which contains the at least one hollow filter element. In this manner, installation tolerances and/or operationally-related vibrations can be better compensated for. The flexible connection can be made of a plastic, in particular an elastomer or rubber.
The filter can advantageously be embodied as an air filter. The air filter can advantageously be part of an air intake system of an internal combustion engine. It can be used for purifying combustion air, which is supplied to the internal combustion engine. However, the invention is not restricted to an air filter of an air intake system of an internal combustion engine of a motor vehicle. Rather, it can also be used in other types of air systems of motor vehicles. The air filter can also be an interior filter. The air filter can also be used outside automotive engineering, in particular in industrial engines.
The hollow filter element according to the invention and the filter according to the invention can advantageously be used in conjunction with an agricultural motor vehicle and/or an agricultural machine. However, the invention is not restricted thereto. It can also be used in other types of motor vehicles, in particular passenger automobiles, trucks, other utility vehicles, or machines, in particular construction vehicles or construction machines.
Instead of filtering air, the invention can also be used for filtering other types of fluids, in particular water, fuel, oil, or urea/water solution.
In one advantageous embodiment, the at least one second housing part, at least in the final mounting state of the filter, can advantageously exert a force, which acts at least axially in relation to the element axis, on the at least one hollow filter element.
The at least one hollow filter element can thus be positioned and/or compressed or clamped in the axial direction in the filter housing with the aid of the second housing part. In particular in combination with at least one seal, which acts at least in the radial direction with respect to the element axis, sealing between the filtered fluid side and the unfiltered fluid side can thus be improved. Furthermore, the holding function and the sealing function can thus each be improved independently of one another.
By combination of a radial incoming flow or outgoing flow with the axial compression or clamping, the ratio between required installation space and filter efficiency can be improved. In particular, the filter can thus be improved with respect to efficiency and space requirement if a double-bellows hollow filter element is used.
The force can advantageously engage from the at least one second housing part on at least one support nub and/or at least one support frame and/or at least one end body and/or at least one seal of the at least one hollow filter element. In this manner, the axial force can be transferred uniformly between the at least one hollow filter element, the first housing part, and the second housing part. The at least one hollow filter element can thus be held stably and precisely in the filter housing.
With the hollow filter element clamped axially between the first housing part and the second housing part, the force conduction through the second housing part can take place via the at least one support nub, the at least one support frame, the at least one end body, and the at least one seal to the first housing part.
In a further advantageous embodiment, the at least one hollow filter element can advantageously comprise at least one spacer element, in particular at least one support nub and/or at least one support web. The outer side of the hollow filter element can thus be held, in particular in the region of an inflow opening or an outflow opening, at a distance to a corresponding inner side of the filter housing. In this manner, using the at least one spacer element, a flow region can be predefined between the at least one hollow filter element and the filter housing, through which fluid can flow.
The at least one spacer element can advantageously be arranged on the at least one end body. The at least one spacer element can comprise at least one support web and/or at least one support nub.
The at least one spacer element can advantageously be integrally connected in particular to the at least one end body. In this manner, it can be produced and/or assembled jointly with the end body.
The at least one spacer element, in the case of a hollow filter element designed as a multiple-bellows hollow filter element, in particular a double-bellows element, can enable the hollow filter element, in particular the double-bellows element, to have radial and axial incoming flow with respect to the element axis. A flow channel or flow chamber can be defined on an unfiltered-fluid-side end side using the at least one first spacer element. The fluid, which first has radial incoming flow with respect to the element axis, can reach a radial inner element interior through the flow channel, after a deflection on the radial outer circumferential side of the at least one hollow filter element, through a corresponding inflow opening on the unfiltered-fluid-side end side of the hollow filter element. From there, the fluid can flow from the radial inside to the radial outside through a corresponding radial inner filter bellows and reach a second, outgoing-flow-side element interior. The second, outgoing-flow-side element interior can advantageously be located radially between the radial outer filter bellows and the radial inner filter bellows.
In a further advantageous embodiment, the at least one hollow filter element can advantageously comprise at least one seal, which can be arranged, with respect to the element axis, at least partially circumferentially in the region of at least one of the end sides of the hollow filter element. The at least one seal can be arranged and embodied so that it can separate an unfiltered fluid side from a filtered fluid side.
In a further advantageous embodiment, the at least one seal can advantageously interact with at least one corresponding sealing surface of a filter housing to form a seal radially with respect to the element axis. In this manner, sealing forces which contribute to the sealing action can act in the radial direction and holding forces which contribute to holding the filter element in the filter housing can act in the axial direction. The sealing function can thus be separated better from the holding function.
In a further advantageous embodiment, the at least one hollow filter element can advantageously have at least one end body on an axial end side with respect to an element axis. The at least one hollow filter element can be supported better on a corresponding end side using the at least one end body. In particular, an axial support with respect to the element axis can be improved.
Furthermore, the at least one end body can be embodied so that it can at least partially close the at least one hollow filter element on the corresponding end side. In this manner, a flow profile into the at least one hollow filter element and out of it can be influenced using the at least one end body.
The at least one end body can advantageously at least comprise at least one end disk or can be embodied as such.
The at least one filter can advantageously comprise at least one secondary filter element.
The at least one secondary filter element can advantageously be arranged downstream of the at least one hollow filter element, i.e., on the filtered-fluid side. Particles which were not captured by the at least one hollow filter element can be filtered out of the fluid stream using the at least one secondary filter element.
The at least one secondary filter element can advantageously comprise a finer filtration, in particular smaller pore sizes, than the at least one hollow filter element. In this manner, smaller particles can also be filtered out using the at least one secondary filter element than is possible using the hollow filter element.
The at least one secondary filter element can be a flat filter element.
The at least one secondary filter element can advantageously be arranged in a space-saving manner at least partially in at least one receptacle of the at least one hollow filter element. The at least one receptacle for the at least one secondary filter element can advantageously be at least partially also formed using the at least one seal and/or at least partially enclosed thereby.
This object is furthermore achieved according to the invention in the hollow filter element in that an element axis of the at least one hollow filter element extends coaxially, axially, or in parallel to an installation/removal axis of the at least one hollow filter element, in relation to which the hollow filter element can be installed through the at least one installation opening into the filter housing and removed from the filter housing in parallel, axially, or coaxially.
The advantages and features disclosed above in conjunction with the filter according to the invention and the advantageous embodiments thereof apply accordingly for the hollow filter element according to the invention and vice versa.
At least one end body can advantageously be arranged on an axial front and/or a rear end side of the hollow filter element with respect to an element axis.
At least one seal can advantageously be arranged at least partially circumferentially in the region of at least one of the end side of the hollow filter element with respect to the element axis.
The at least one seal can advantageously comprise at least one partially circumferential radial outer and/or radial inner seal section, which can interact with at least one corresponding sealing surface of a filter housing of the filter to form a seal radially with respect to the element axis. The at least one seal can be attached in the region of an axial end side. The sealing can advantageously be performed in the radial direction with respect to the element axis. In this manner, the seal can be separated with respect to force from a possible axial support of the hollow filter element, in the filter housing. The support and the sealing can thus each be improved per se.
The hollow filter element can advantageously be a round filter element having a round cross section, an oval filter element having an oval cross section, a flat-oval round filter element having a flattened oval cross section, a conical round filter element, in which the round cross section tapers in the axial direction in relation to the main axis, a conical-oval round filter element, in which the oval cross section tapers in the axial direction at least in the direction of a transverse axis, a conical flat-oval round filter element, in which the flat-oval cross section tapers in the axial direction at least in the direction of a transverse axis, or a hollow filter element having another type, in particular a polygonal, cross section and/or another type of axial cross-sectional profile in the direction of the main axis.
The hollow filter element can advantageously be a multiple-bellows hollow filter element, which has at least two filter bellows placed radially one inside the other. At least one element interior can be formed, in particular delimited, between the filter bellows. Such a multiple-bellows hollow filter element can be referred to as a double-bellows filter element. The filter bellows can each be embodied in accordance with an above-described hollow filter element.
At least two filter bellows of a multiple-bellows hollow filter element can advantageously be mechanically connected to one another by means of at least one end body and/or at least one support body. The filter bellows can be connected to one another on at least one axial front and/or one rear end side with respect to an element axis of the at least one hollow filter element.
At least one element interior can advantageously be used as a flow chamber for the fluid to be filtered. The at least one flow chamber can be connected to an end side of the hollow filter element. The flow chamber can be used both for discharging the filtered fluid and also for introducing unfiltered fluid.
Each of at least two filter bellows, which are placed radially one inside another, can be designed as a star filter having filter folds, which are arranged in a star shape and extend in the radial direction, having axially extending end edges. The radial inner end edges of the folds of the radial outer filter bellows and the radial outer end edges of the folds of the radial inner filter bellows can each delimit the at least one element interior, in particular the flow chamber.
In a double-bellows filter element, alternatively, the radial inner filter bellows can also be composed of at least two open, in particular flat and/or planar, filter bellows or filter elements, so-called flat filter elements. Additionally or alternatively, the radial outer filter bellows can also be composed of at least two open, in particular flat and/or planar filter elements.
At least one filter medium of at least one filter bellows can advantageously be circumferentially closed or open with respect to the element axis. The filter medium can in particular be folded or curved in a star shape, preferably in a zigzag or corrugated form. The filter medium can also be non-folded or non-curved.
At least one filter medium can at least comprise filter paper, filter nonwoven material, or another type of filter medium suitable for filtering the fluid. At least one filter medium can be single-layer or multilayered.
In a double-bellows filter element embodied as a round filter element, the radial inner circumferential side of the radial outer filter bellows and the radial outer circumferential side of the radial inner filter bellows can advantageously extend in parallel or diagonally in relation to one another, in particular conically. A radial outer element interior, in particular an outgoing-flow-side element interior, can be implemented between the radial outer circumferential side of the radial inner filter bellows and the radial inner circumferential side of the radial outer filter bellows. A radial inner element interior, in particular an incoming-flow-side element interior, can be implemented inside the radial inner filter bellows. For the filtration, the fluid can pass from the radial outside to the radial inside through the radial outer filter bellows to the radial outer element interior. The radial inner element interior can be closed on one end side of the double-bellows filter element and can be open on the opposite end side, in particular an incoming-flow-side end side. A part of the inflowing fluid can be deflected, in particular by 90°, on the radial outer circumferential side of the radial outer filter bellows. The deflected part of the fluid can flow through a fluid guiding region along the incoming-flow-side or unfiltered-fluid-side end side to an intake opening. The fluid can pass into the radial inner element interior through the intake opening on the incoming-flow-side end side. The fluid can flow through the radial inner filter bellows from the radial inner element interior to the radial outer element interior and can pass therefrom through corresponding outlet openings in the filtered-fluid-side end side out of the double-bellows filter element.
Alternatively, the hollow filter element can advantageously comprise a single filter bellows. The filter bellows can comprise at least one filter medium, through which flow can occur for filtering of the fluid. An element interior of the filter bellows can be closed on one end side using an end body in particular.
The at least one end body can advantageously at least comprise an end disk. The at least one end body can advantageously at least comprise plastic. The at least one end body can advantageously at least comprise polyurethane, in particular polyurethane foam. The at least one end body can advantageously be at least partially flexible, in particular elastic.
At least one end body can advantageously be permanently connected to at least one of the filter bellows.
The at least one end body can advantageously be connected to the filter bellows in a materially-bonded and/or friction-locked and/or formfitting manner, in particular by means of an adhesive bond, welded bond, a mechanical connection, in particular a plug connection, clamp connection, and/or by means of snapping in. The at least one end body can also be extruded or injection-molded, cast, or foamed onto the at least one filter bellows.
The at least one seal on the at least one end side can implement a seal between the hollow filter element and the filter housing.
The at least one seal can be used in particular for the flow-tight separation of an unfiltered fluid side from a filtered fluid side of the hollow filter element. It can prevent faulty fluid streams, which could impair an efficiency of the filter.
The at least one seal can advantageously comprise at least one sealing ring. The at least one seal section can be located on the radial outside or radial inside on the at least one sealing ring. The at least one sealing ring, in particular the at least one sealing section, can advantageously be circumferentially coherent. It can thus seal in a circumferentially closed manner.
The at least one seal can advantageously be connected integrally or in multiple pieces to the at least one end body. The at least one seal can advantageously be extruded or injection-molded on the at least one end body or implemented as a two-component part therewith.
The at least one seal can advantageously be at least partially flexible, in particular elastic. A sealing action can be improved in this manner. Furthermore, the at least one seal can better compensate for installation-related and/or operation-related tolerances and/or vibrations.
The at least one seal can advantageously be made of an elastic material or comprise such a material. The at least one seal can advantageously comprise polyurethane or another type of plastic, which is elastic in particular.
The at least one seal can advantageously comprise at least two seal sections having/made of identical materials and/or identical hardnesses. Alternatively, the at least one seal can comprise at least two seal sections having/made of different materials and/or different hardnesses. In this manner, a sealing action and/or a stability of the at least one seal can be improved. The at least one seal can advantageously be softer at least in a first seal section than in a second seal section. The at least one second seal section is arranged axially closer, with respect to the element axis, to the filter bellows than the at least one first seal section. The at least one seal can advantageously be harder in the region of a seal section on the unfiltered-fluid side, in particular the unfiltered-air side, than in the region of a seal section on the filtered-fluid side, in particular the filtered-air side.
The at least one seal can advantageously be supported at least sectionally using at least one support section. The at least one support section can advantageously be connected to at least one end body or at least can also be formed thereby. The at least one support section can advantageously at least sectionally support the at least one seal in a seal section which is soft in comparison to the remainder of the seal. The at least one support section can act as a reinforcement of the at least one seal.
The at least one seal can advantageously be or comprise a radial seal.
The at least one seal can advantageously be located outside of incoming-flow surfaces and outgoing-flow surfaces of the filter media, through which flow can occur. It can advantageously be located outside the filter lateral surfaces of the hollow filter element.
An installation/removal axis of the filter, in relation to which the hollow filter element can be installed into the filter housing and can be removed from the filter housing in parallel, axially, or coaxially, can advantageously extend axially, coaxially, or in parallel to the element axis. In this manner, the hollow filter element can be moved into the filter housing or out of it in an axial direction with respect to the element axis. The hollow filter element can be held, in particular clamped or chucked, in the filter housing in the axial direction with respect to the element axis. A radial compression of the at least one seal can be reduced in this case. A mechanical strain of the at least one seal can thus be reduced. Furthermore, the risk can thus be reduced that the at least one seal will deform in an undesired manner during the installation of the hollow filter element. A sealing action can be impaired by undesired deformation.
At least one end body can advantageously at least partially close at least the corresponding end side of the hollow filter element. In this manner, a fluid flow through the end side can be restricted or prevented. A flow profile in/on the hollow filter element can thus be predefined using the at least one end body.
The at least one seal can advantageously comprise at least two seal sections, which are spaced apart from one another at least axially with respect to the element axis. In this manner, two sealed regions which are axially spaced apart from one another can be implemented using the at least one seal.
In conjunction with an axial installation/removal axis of the filter, during the installation of the hollow filter element, firstly the axial front seal section in the installation direction can form a seal in relation to a corresponding sealing surface of the filter housing. Subsequently, the hollow filter element can be pushed further in the installation direction into the filter housing, in particular by mounting of a housing cover. In this case, at least one rear seal section can interact with the corresponding sealing surface of the filter housing. All seal sections can act to form a radial seal in the end position of the hollow filter element.
Furthermore, a redundancy can be created by the use of at least two seal sections. The sealing action and the reliability of the at least one seal can thus be further improved.
The at least one seal can advantageously at least comprise a double radial seal. The at least one seal can comprise a double radial seal or can be a double radial seal. In the double radial seal, two parallel seal sections are each circumferentially closed coherently with respect to the element axis. A sealing action can be improved further in this manner. Furthermore, a uniform seal can be produced in the circumferential direction.
The at least one seal can advantageously at least sectionally radially, with respect to the element axis, protrude beyond at least one radial outer filter bellows and/or at least one end body. In this manner, the at least one seal, in particular at least one sealing section, can be arranged on the radial outside on the hollow filter element. It can thus define the widest point of the hollow filter element with respect to the element axis. A free chamber, which can act as a flow chamber, can thus be defined between the radial outermost region of the at least one seal and the corresponding radial outer filter bellows.
The at least one seal can advantageously protrude axially beyond at least one of the filter bellows and/or at least one end body with respect to the element axis. In this manner, the at least one seal can define an axial outermost end of the hollow filter element.
The at least one seal, in particular a free end edge of the at least one seal, can advantageously in the axial direction as a stop of the hollow filter element. The at least one seal can stop on a corresponding housing region in an end position of the hollow filter element and thus delimit a movement axially in relation to the element axis. The hollow filter element can thus be placed more accurately and stably in the filter housing.
At least one support body, in particular a support frame, can advantageously be provided at least to support at least one end body and/or the at least one seal. A shape of the hollow filter element can be predefined and/or stabilized using the at least one support body. In its installed state, the hollow filter element can be better supported in the filter housing using the at least one support body. Holding forces acting on the hollow filter element can thus be introduced and distributed more uniformly into the hollow filter element and conducted out of it.
At least one of the end bodies can be supported using the at least one support body. A shape of a flexible end body can advantageously be stabilized using the at least one support body.
The at least one support body can additionally or alternatively support the at least one seal. In this manner, corresponding radial sealing forces can be introduced better into the at least one seal and/or relayed therefrom.
The at least one support body can advantageously be at least partially embedded in at least one end body and/or the at least one seal. A more stable connection can be implemented in this manner.
The at least one support body can advantageously have at least one latticed section. In this manner, it can easily be enclosed, in particular extrusion-coated or cast, using the material of the at least one end body and/or the at least one seal.
The at least one support body can advantageously at least comprise at least one support frame.
The at least one support body can advantageously comprise at least one section which extends radially with respect to the element axis. The at least one radially extending section can extend in and/or on at least one end body and/or the at least one seal. The at least one radially extending section can advantageously support the at least one end body and/or the at least one seal.
The at least one support body can advantageously comprise at least one section which extends axially with respect to the element axis. The at least one axially extending section can advantageously extend between the end sides of the filter element. It can improve the axial stability of the filter element. Furthermore, the at least one axially extending section can support at least one circumferential side of at least one of the filter bellows in the radial direction.
The at least one support body, in particular a support frame, can advantageously be integrally implemented.
The at least one support body can advantageously be at least partially cast or injection-molded from plastic in particular.
In particular using the at least one axial section of the at least one support body, axial forces, which can arise during the compression of the hollow filter element in the filter housing, can advantageously be introduced.
A hollow, in particular tubular support body can advantageously have at least one support strut. At least one support strut can advantageously be located in the region of an end of the support body. At least one support strut can advantageously be arranged in the region of the end which faces toward the outlet-side end side of the hollow filter element. At least one support strut can advantageously extend transversely, in particular perpendicularly, in relation to the element axis. In the case of an end body having an oval cross section, at least one support strut can extend in the direction of the short transverse axis of the oval support body and transversely, in particular perpendicularly, in relation to the element axis. At least one support strut can extend transversely through the element interior of at least one filter bellows. At least one support strut can be used for supporting the sides of the filter bellows, in an oval filter bellows, the long flat sides of the filter bellows.
The at least one seal can advantageously also form at least one receptacle, in particular a receptacle chamber, for at least one section of at least one secondary filter element of the filter. The at least one secondary filter element can be arranged in a simple and/or space-saving manner in the filter housing by means of the at least one receptacle. Furthermore, the secondary filter element can be placed more easily in relation to the hollow filter element with the aid of the at least one receptacle.
The secondary filter element can advantageously be a so-called flat filter element. In a flat filter element, the filter medium does not enclose an element interior, in contrast to a hollow filter element. The flat filter element can be planar or curved in this case.
The object is additionally achieved according to the invention by the filter housing in that a housing axis, to which an element axis of the at least one hollow filter element can be arranged coaxially, axially, or in parallel, extends coaxially, axially, or in parallel to an installation/removal axis of the at least one hollow filter element, to which the hollow filter element can be installed through the at least one installation opening into the filter housing and removed from the filter housing in parallel, axially, or coaxially.
The advantages and features listed above in conjunction with the filter according to the invention, the hollow filter element according to the invention, and the respective advantageous embodiments thereof apply for the filter housing according to the invention and the advantageous embodiments thereof and vice versa.
The object is finally achieved according to the invention by the seal according to the invention.
The advantages and features listed above in conjunction with the hollow filter element according to the invention, the filter according to the invention, and the filter housing according to the invention and the respective advantageous embodiments thereof apply accordingly for the seal according to the invention and vice versa.
Identical parts are provided with identical reference signs in the figures.